diff --git a/backend/app/Http/Controllers/Api/AuthenticationTrait.php b/backend/app/Http/Controllers/Api/AuthenticationTrait.php
index 447641df..bb72f283 100644
--- a/backend/app/Http/Controllers/Api/AuthenticationTrait.php
+++ b/backend/app/Http/Controllers/Api/AuthenticationTrait.php
@@ -26,12 +26,7 @@ trait AuthenticationTrait {
 
         if ($this->getGuard() == 'children') {
             Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-                try {
-                    return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-                } catch (\Throwable $e) {
-                    Log::critical($e->getMessage());
-                    return false;
-                }
+                return $this->telsize($value);
             });
         }
 
diff --git a/backend/app/Http/Controllers/Api/ChildrenController.php b/backend/app/Http/Controllers/Api/ChildrenController.php
index 17fc5b57..1cdffa90 100644
--- a/backend/app/Http/Controllers/Api/ChildrenController.php
+++ b/backend/app/Http/Controllers/Api/ChildrenController.php
@@ -32,12 +32,7 @@ class ChildrenController extends Controller {
     public function registerTemporary (Request $r) {
         // 電話番号の文字数。
         Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->telsize($value);
         });
 
         $validate = Validator::make($r->all(), [
@@ -54,7 +49,7 @@ class ChildrenController extends Controller {
             return ['status_code' => 400, 'error_messages' => ['既に使用されている電話番号です。']];
         }
 
-        $token = bin2hex(random_bytes(8));
+        $token = bin2hex(random_bytes(24));
         $create = [
             'type' => 0,
             'tel' => $r->tel,
@@ -104,28 +99,12 @@ KIKI承知システムを使って「聞いてない！」「言ってない！
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                if (is_null($value)) return true;
-                return strlen($value) < env('PDF_MAX_SIZE');
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesizecannull($value);
         });
-    
+
         // ミームタイプ
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                if (is_null($value)) return true;
-                return (
-                    mime_content_type($value) == 'image/jpeg' || // jpg
-                    mime_content_type($value) == 'image/png'  || // png
-                    mime_content_type($value) == 'image/gif'     // gif
-                );
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememecannull($value);
         });
 
         $validate = Validator::make($r->all(), [
@@ -187,12 +166,7 @@ KIKI承知システムを使って「聞いてない！」「言ってない！
     public function requestPassword (Request $r) {
         // 電話番号の文字数。
         Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->telsize($value);
         });
 
         $validate = Validator::make($r->all(), [
@@ -209,7 +183,7 @@ KIKI承知システムを使って「聞いてない！」「言ってない！
             return ['status_code' => 400, 'error_messages' => ['電話番号が未登録です。入力した情報を確認してください。']];
         }
 
-        $token = bin2hex(random_bytes(8));
+        $token = bin2hex(random_bytes(24));
         $create = [
             'type' => 1,
             'child_id' => $result->id,
@@ -386,26 +360,12 @@ KIKI承知システムを使って「聞いてない！」「言ってない！
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen(base64_decode($value)) < env('PDF_MAX_SIZE');
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesize($value);
         });
 
         // ミームタイプ
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                return (
-                    mime_content_type($value) == 'image/jpeg' || // jpg
-                    mime_content_type($value) == 'image/png'  || // png
-                    mime_content_type($value) == 'image/gif'     // gif
-                );
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememe($value);
         });
 
         // バリデーションエラー
@@ -453,12 +413,7 @@ KIKI承知システムを使って「聞いてない！」「言ってない！
 
         // 電話番号の文字数。
         Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->telsize($value);
         });
 
         // バリデーションエラー
diff --git a/backend/app/Http/Controllers/Api/FathersController.php b/backend/app/Http/Controllers/Api/FathersController.php
index ffe1f2d6..9e595748 100644
--- a/backend/app/Http/Controllers/Api/FathersController.php
+++ b/backend/app/Http/Controllers/Api/FathersController.php
@@ -49,7 +49,7 @@ class FathersController extends Controller {
             return ['status_code' => 400, 'error_messages' => ['メールアドレスが未登録です。入力した情報を確認してください。']];
         }
 
-        $token = bin2hex(random_bytes(8));
+        $token = bin2hex(random_bytes(24));
         $create = [
             'type' => 1,
             'father_id' => $result->id,
@@ -98,7 +98,7 @@ class FathersController extends Controller {
             return ['status_code' => 400, 'error_messages' => ['入力したメールアドレスは既に登録済みです。同じメールアドレスは使用できません。']];
         }
         else {
-            $token = bin2hex(random_bytes(8));
+            $token = bin2hex(random_bytes(24));
             $create = ['email' => $r->email, 'token' => $token, 'ttl' => date('Y-m-d H:i:s', time()+env('TTL_SEC'))];
 
             try {
@@ -121,38 +121,17 @@ class FathersController extends Controller {
     public function registerMain (Request $r) {
         // 電話番号の文字数。
         Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->telsize($value);
         });
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                if (is_null($value)) return true;
-                return strlen($value) < env('PDF_MAX_SIZE');
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesizecannull($value);
         });
-    
+
         // ミームタイプ
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                if (is_null($value)) return true;
-                return (
-                    mime_content_type($value) == 'image/jpeg' || // jpg
-                    mime_content_type($value) == 'image/png'  || // png
-                    mime_content_type($value) == 'image/gif'     // gif
-                );
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememecannull($value);
         });
 
         $validate = Validator::make($r->all(), [
@@ -309,26 +288,12 @@ class FathersController extends Controller {
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen(base64_decode($value)) < env('PDF_MAX_SIZE');
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesize($value);
         });
 
         // ミームタイプ
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                return (
-                    mime_content_type($value) == 'image/jpeg' || // jpg
-                    mime_content_type($value) == 'image/png'  || // png
-                    mime_content_type($value) == 'image/gif'     // gif
-                );
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememe($value);
         });
 
         // バリデーションエラー
@@ -390,12 +355,7 @@ class FathersController extends Controller {
 
         // 電話番号の文字数。
         Validator::extend('tel_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen((string)$value) == 10 || strlen((string)$value) == 11;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->telsize($value);
         });
 
         // バリデーションエラー
diff --git a/backend/app/Http/Controllers/Api/MeetingImagesController.php b/backend/app/Http/Controllers/Api/MeetingImagesController.php
index dfb9b857..c3397c67 100644
--- a/backend/app/Http/Controllers/Api/MeetingImagesController.php
+++ b/backend/app/Http/Controllers/Api/MeetingImagesController.php
@@ -22,26 +22,12 @@ class MeetingImagesController extends Controller {
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                return strlen(base64_decode($value)) < env('PDF_MAX_SIZE');
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesize($value);
         });
 
         // ミームタイプ
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                return (
-                    mime_content_type($value) == 'image/jpeg' || // jpg
-                    mime_content_type($value) == 'image/png'  || // png
-                    mime_content_type($value) == 'image/gif'     // gif
-                );
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememe($value);
         });
 
         // バリデーションエラー
diff --git a/backend/app/Http/Controllers/Api/MeetingsController.php b/backend/app/Http/Controllers/Api/MeetingsController.php
index 20f287ca..3883dfe0 100644
--- a/backend/app/Http/Controllers/Api/MeetingsController.php
+++ b/backend/app/Http/Controllers/Api/MeetingsController.php
@@ -27,67 +27,18 @@ class MeetingsController extends Controller {
 
         // ファイルサイズは10MiB以内
         Validator::extend('image_size', function ($attribute, $value, $params, $validator) {
-            try {
-                $ok = true;
-                foreach (json_decode($value) as $v) {
-                    if (strlen(base64_decode($v)) > env('PDF_MAX_SIZE')) {
-                        $ok = false;
-                    }
-                }
-                return $ok;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagesizemulti($value);
         });
 
         // ミームタイプ
         //// 画像
         Validator::extend('image_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                $ok = true;
-                foreach (json_decode($value) as $v) {
-                    if (substr($v, -5) == '.jpeg' || substr($v, -4) == '.jpg' || substr($v, -4) == '.png' || substr($v, -4) == '.gif') {
-                        if (
-                            substr($v, -5) != '.jpeg' && // jpeg
-                            substr($v, -4) != '.jpg'  && // jpg
-                            substr($v, -4) != '.png'  && // png
-                            substr($v, -4) != '.gif'     // gif
-                        ) {
-                            $ok = false;
-                        }
-                    }
-                    else {
-                        if (
-                            mime_content_type($v) != 'image/jpeg' && // jpg
-                            mime_content_type($v) != 'image/png'  && // png
-                            mime_content_type($v) != 'image/gif'     // gif
-                        ) {
-                            $ok = false;
-                        }
-                    }
-                }
-
-                return $ok;
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->imagememeorfile($value);
         });
 
         //// PDF
         Validator::extend('pdf_meme', function ($attribute, $value, $params, $validator) {
-            try {
-                if (substr($value, -4) != '.pdf') {
-                    return mime_content_type($value) == 'application/pdf';
-                }
-                else {
-                    return substr($value, -4) == '.pdf';
-                }
-            } catch (\Throwable $e) {
-                Log::critical($e->getMessage());
-                return false;
-            }
+            return $this->pdfmeme($value);
         });
 
         $validate = Validator::make($r->all(), [
@@ -700,26 +651,9 @@ class MeetingsController extends Controller {
         }
 
         // ミームタイプ
-        if (substr($r->pdf, -4) != '.pdf') {
-            Validator::extend('pdf_meme', function ($attribute, $value, $params, $validator) {
-                try {
-                    return mime_content_type($value) == 'application/pdf';
-                } catch (\Throwable $e) {
-                    Log::critical($e->getMessage());
-                    return false;
-                }
-            });
-        }
-        else {
-            Validator::extend('pdf_meme', function ($attribute, $value, $params, $validator) {
-                try {
-                    return substr($value, -4) == '.pdf';
-                } catch (\Throwable $e) {
-                    Log::critical($e->getMessage());
-                    return false;
-                }
-            });
-        }
+        Validator::extend('pdf_meme', function ($attribute, $value, $params, $validator) {
+            return $this->pdfmeme($value);
+        });
 
         $validate = Validator::make($r->all(), [
             'title' => 'required|max:100',
diff --git a/backend/app/Http/Controllers/Controller.php b/backend/app/Http/Controllers/Controller.php
index c948e6ee..cfc024f8 100644
--- a/backend/app/Http/Controllers/Controller.php
+++ b/backend/app/Http/Controllers/Controller.php
@@ -6,6 +6,7 @@ use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
 use Illuminate\Foundation\Bus\DispatchesJobs;
 use Illuminate\Foundation\Validation\ValidatesRequests;
 use Illuminate\Routing\Controller as BaseController;
+use Illuminate\Support\Facades\Log;
 
 class Controller extends BaseController
 {
@@ -16,8 +17,7 @@ class Controller extends BaseController
      * @return string
      * @throws \Exception
      */
-    public function uuidv4 () : string
-    {
+    public function uuidv4 () : string {
         $chars = str_split('xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx');
 
         foreach ($chars as $i => $char) {
@@ -30,4 +30,101 @@ class Controller extends BaseController
 
         return implode('', $chars);
     }
+
+    public function telsize ($value) {
+        try {
+            return strlen((string)$value) == 10 || strlen((string)$value) == 11;
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
+
+    public function imagesize ($value) {
+        try {
+            return strlen($value) < env('PDF_MAX_SIZE');
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
+
+    public function imagesizecannull ($value) {
+        if (is_null($value)) return true;
+        return $this->imagesize($value);
+    }
+
+    public function imagememe ($value) {
+        try {
+            return (
+                mime_content_type($value) == 'image/jpeg' || // jpg
+                mime_content_type($value) == 'image/png'  || // png
+                mime_content_type($value) == 'image/gif'     // gif
+            );
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
+
+    public function imagememecannull ($value) {
+        if (is_null($value)) return true;
+        return $this->imagememe($value);
+    }
+
+    public function imagememeorfile ($value) {
+        try {
+            $ok = true;
+            foreach (json_decode($value) as $v) {
+                if (substr($v, -5) == '.jpeg' || substr($v, -4) == '.jpg' || substr($v, -4) == '.png' || substr($v, -4) == '.gif') {
+                    if (
+                        substr($v, -5) != '.jpeg' && // jpeg
+                        substr($v, -4) != '.jpg'  && // jpg
+                        substr($v, -4) != '.png'  && // png
+                        substr($v, -4) != '.gif'     // gif
+                    ) {
+                        $ok = false;
+                    }
+                }
+                else {
+                    $ok = $this->imagememe($v);
+                }
+            }
+
+            return $ok;
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
+
+    public function imagesizemulti ($value) {
+        try {
+            $ok = true;
+            foreach (json_decode($value) as $v) {
+                if (strlen(base64_decode($v)) > env('PDF_MAX_SIZE')) {
+                    $ok = false;
+                }
+            }
+            return $ok;
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
+
+
+    public function pdfmeme ($value) {
+        try {
+            if (substr($value, -4) != '.pdf') {
+                return mime_content_type($value) == 'application/pdf';
+            }
+            else {
+                return substr($value, -4) == '.pdf';
+            }
+        } catch (\Throwable $e) {
+            Log::critical($e->getMessage());
+            return false;
+        }
+    }
 }
diff --git a/backend/database/migrations/2021_08_13_020003_create_email_activations_table.php b/backend/database/migrations/2021_08_13_020003_create_email_activations_table.php
index 7e66cb59..54b04c74 100644
--- a/backend/database/migrations/2021_08_13_020003_create_email_activations_table.php
+++ b/backend/database/migrations/2021_08_13_020003_create_email_activations_table.php
@@ -18,7 +18,7 @@ class CreateEmailActivationsTable extends Migration
             $table->unsignedTinyInteger('type');
             $table->unsignedBigInteger('father_id')->nullable();
             $table->string('email', 255)->unique();
-            $table->string('token', 16);
+            $table->string('token', 64)->unique();
             $table->dateTime('ttl');
             $table->timestamps();
         });
diff --git a/backend/database/migrations/2021_08_13_050204_create_tel_activations_table.php b/backend/database/migrations/2021_08_13_050204_create_tel_activations_table.php
index 45bb45ef..6428ca31 100644
--- a/backend/database/migrations/2021_08_13_050204_create_tel_activations_table.php
+++ b/backend/database/migrations/2021_08_13_050204_create_tel_activations_table.php
@@ -19,7 +19,7 @@ class CreateTelActivationsTable extends Migration
             $table->unsignedBigInteger('child_id')->nullable();
             $table->foreign('child_id')->references('id')->on('children')->onDelete('cascade');
             $table->string('tel', 11)->unique();
-            $table->string('token', 100);
+            $table->string('token', 100)->unique();
             $table->dateTime('ttl');
             $table->timestamps();
         });